Fix @_required directive when the schema is available

[AndrewIngram]

If graphcache was configured with the full schema, the @_required directive would be ignored on nullable fields. This diff tweaks the condition to fix that behaviour.

[changeset-bot]

🦋 Changeset detected

Latest commit: a910c50

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@urql/exchange-graphcache	Minor

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[JoviDeCroock]

Mind adding a test and changeset?

[AndrewIngram]

Should be able to, will actually need to check out the code first 😅

Can I just get confirmation that this is actually fixing unintended behaviour? The docs are a little confusing on this point, even though required seems most useful when there's a schema saying a field is optional:

Graphcache comes with two directives built-in by default. The optional and required directives. These directives can be used as an alternative to the Schema Awareness feature’s ability to generate partial result

[AndrewIngram]

Okay, should be good to go 🤞🏻

[kitten]

Can I just get confirmation that this is actually fixing unintended behaviour?

I'd say it's unintended behaviour, yes. It's definitely not something we had in mind, since the directives were mostly tested as an alternative to schema awareness.